Objective The Tonghua region in the east of the Songliao Basin is a high-risk and blank area of petroleum exploration.The unrevealed key problems including the growth of source rocks,hydrocarbon generation potential and oil and gas source and the low exploration degree have constrained the further study of petroleum geological conditions and exploration deployment.Based on outcrop and core observations,geological section survey,trench Objective The Tonghua region in the east of the Songliao Basin is a high-risk and blank area of ​​petroleum exploration. The unrevealed key problems include the growth of source rocks, hydrocarbon generation potential and oil and gas source and the low exploration degree have constrained the further study of petroleum geological conditions and exploration deployment.Based on outcrop and core observations, geological section survey, trench